<h2>memory_object_data_unavailable</h2><hr><p><strong>Function</strong> - Instruct kernel to zero-fill pages as requested data does not exist.
<h3>SYNOPSIS</h3><pre><strong>kern_return_t memory_object_data_unavailable</strong><strong>(memory_object_control_t</strong><var>memory_control</var>,
<strong>vm_offset_t</strong><var>offset</var>,
<strong>vm_size_t</strong><var>size</var><strong>);</strong></pre><h3>PARAMETERS</h3><dl><p><dt><var>memory_control</var><dd>
[in memory-cache-control send right]
The memory cache control port
to be used by the memory manager for cache management requests.
This port is provided by the kernel in a <strong>memory_object_init</strong> or a
<strong>memory_object_create</strong> call.
<p><dt><var>offset</var><dd>
[in scalar]
The offset within the memory object, in bytes.
<p><dt><var>size</var><dd>
[in scalar]
The number of bytes of data (starting at <var>offset</var>). The number
must convert to an integral number of memory object pages.
</dl><h3>DESCRIPTION</h3><p>
The <strong>memory_object_data_unavailable</strong> function indicates
that the memory
manager cannot provide the kernel with the data requested for
the given region.
Instead, the kernel should provide the data for this region.
<p>
A memory manager can use this call in any of the following situations:
<ul><li>
When the object was created by the kernel
(via <strong>memory_object_create</strong>) and
the kernel has not yet provided data for the region (via either
<strong>memory_object_data_initialize</strong> or <strong>memory_object_data_return</strong>).
In this case, the
object is a temporary memory object; the memory manager is the default
memory manager; and the kernel should provide zero-filled pages for the
object.
<p><li>
When the object is a normal user-created memory object. In this case, the
kernel should provide zero-filled pages for the region.
</ul><h3>RETURN VALUES</h3><p>
Only generic errors apply.
<h3>RELATED INFORMATION</h3><p>
Functions:
<a href="memory_object_create.html"><strong>memory_object_create</strong></a>,
<a href="memory_object_data_error.html"><strong>memory_object_data_error</strong></a>,
<a href="memory_object_data_request.html"><strong>memory_object_data_request</strong></a>,
<a href="memory_object_data_supply.html"><strong>memory_object_data_supply</strong></a>.